IT HAS become the best-known finding of the plethora of polls and surveys conducted in advance of the referendum.
According to the Scottish Social Attitudes survey, no less than 65 per cent of Scots would be in favour of independence if they thought that leaving the UK would result on average in everyone being £500 a year better off, while only 21 per cent would be opposed.
Forget all the arguments about a shared British identity or 300 years of common history, Scots were apparently prepared to give all that up if the price were right.
The politicians seem to have taken the lesson to heart. Just a few weeks ago the Yes side was arguing that independence would result in everyone on average being a £1,000 a year better off, while on the very same day the No camp was suggesting that staying in the Union would deliver a £1,400 a year dividend. Both sides seem to have accepted that they need to appeal to our wallet.
On its own, however, the £500 finding can be regarded with scepticism. Voters are not necessarily good judges of how they would behave in a hypothetical situation. But lying alongside it is a crucial current reality – no other issue distinguishes Yes and No supporters more than what they think the economic consequences of independence would be.
In the most recent ICM poll for this newspaper, for example, no less than 86 per cent of those who said that independence would be good for Scotland’s economy went on to say that they intended to vote Yes. Conversely, as many as 85 per cent of those who believe that independence would be bad for the nation’s economy stated that they would vote No.
So whatever we make of their answers to a hypothetical £500 scenario, what voters think the economic consequences of independence would be appears to be central to the decisions they are actually making. Consequently it looks as though that for both sides the key to winning the referendum lies in persuading voters of the economic merits of their case.
Herein lies a problem for the Yes side – they have so far failed to convince most voters that independence would be good for Scotland’s economy. As the table above shows, still no more than 35 per cent are of that view – no more than back in January. They are clearly outnumbered by the 45 per cent who reckon independence would be bad for the economy, a figure that is slightly higher now than at the beginning of the year.
But not all of the economic arguments have gone the way the No side might have hoped. That is certainly true of the dramatic announcement in February that no current or future UK government would be willing to share the pound as part of a monetary union with an independent Scotland.
The No campaign anticipated that this claim would see undecided voters flock to their side in horror.
Their expectations were dashed – for two reasons.
First, voters were not presuming that a monetary union would necessarily happen. According to a Panelbase poll conducted just days before the currency announcement, only 41 per cent expected such a union to be formed.
Second, the Yes side succeeded in persuading many voters that the UK could not afford to deny Scotland the pound and thus was bluffing. YouGov recently reported that no less than 42 per cent are still of that view.
Important though it may be, winning the economic argument is not necessarily proving easy.
• John Curtice is Professor of Politics at Strathclyde University